Attention is directed to a masters thesis by one of the inventors herein entitled "Development of a Diver Operated Underwater Arc Stud Welding System" (M.I.T. 1982) herein incorporated by reference.
Prior art underwater welding techniques can be characterized as either dry or wet. In dry underwater welding a water-free habitat is constructed about the surface to be welded and then conventional methods are followed. See, for examples, U.S. Pat. No. 3,989,920 issued to Masubuchi et al on Nov. 2, 1976 and U.S. Pat No. 4,069,408 issued to Masubuchi et al on Jan. 17, 1978. In wet welding, the arc is struck through the water in order to melt the metal surface to be welded. Wet weld joints tend to be erractic and the operation is slow and laborious.
There exists a need for better wet welding techniques, particularly for welding of metal studs to metal walls. An apparatus for welding studs to walls efficiently would find use in repairs of vessels and other structure at sea, seawall reconstruction and other applications.